Into the lands ? With pics of my specific 6 ARC load

[morning would]

So I have spent a metric shit ton of time researching loading depths based on using a modified case and the Hornady tool to find where the cartridge/bullet combo jams. I’ve seen all kinds of terminology, but no pics. So figured I’d ask a question on one of the most knowledgeable sites on the net, and use a pic for an example.

Rifle is an AR in 6 ARC. It’s built by APF with a CF Proof Research barrel. Found a few loads that get me to .7-ish at best, but I know it’s got more in it. Grabbed the OAL gauge and hard jammed a 105 Berger and came up with base to ogive of 1.718. Came off that hard jam by .010, so base to ogive is now 1.708, and single loaded it into a mag and sent the bolt home with the bolt release. Was trying to make sure that if it was going to stick, I’d have it happen at home where I can clean up the mess easier. Did this with 3 loaded rounds separately and none of them stuck a bullet. I assumed they wouldn’t, but I am trying to get these rounds as perfect as my ability allows. Anyways, all of them have marks on them. Marks that tell me it’s touching the lands, but not hanging up the bullet. 6 ARC is pretty finicky in how fast it builds pressure, so I am about 1.3 grains down from max at 24.8 grains of TAC. Just looking for advice, I know to take all of it in and every rifle is different, but just don’t want to blow shit up. Pretty sure I’m safe, but nobody around the net posts pics of what I’m talking about, so maybe this will help others someday in a search.

Generally speaking, when you are still touching the lands enough to make these marks, is that truly .010 off the lands? Or should I see absolutely zero marks on the bullet before it’s not considered “jamming“ the lands? I know this round does not fit in a mag and will have to single load from the top. I’m fine with that for paper punching. I’ll adjust later, maybe, to fit in a magazine if I choose to use this for anything more than a target shooter. Just trying to see how accurate I can truly get a load to be for this particular rifle.

I appreciate you guys taking a look at the pic, and giving me an education of what the correct terminology it is that I’m looking at.

 

[acudaowner]

your into the lands yep deep up in there , scientific terms the witchy dalla do hickey thing is up in t ere how does it shoot ?

 

[morning would]

your into the lands yep deep up in there , scientific terms the witchy dalla do hickey thing is up in t ere how does it shoot ?

No idea. Gonna shoot it Saturday.

 

[redbullitt]

Sharpie your bullets then find the lands with them. Much easier to see when you contact them without having to hit em so hard. Whenever ive done it this way, you can see the rifling start to leave marks parallel to the base and tip of bullet that look just like rifling. Very easy to see that way while BARELY contacting the lands.

Why jam so much? I doubt it will prove necessary fwiw. One notable exception is with bore riding cast bullets for me, but thats another animal.... anyways, It SUCKS to have to single load and then you pull a bullet and powder up the raceway... they dont stick now when its clean at home but Murphy... man he likes it dirty...

Have you tried any good factory match ammo to get a baseline? It SHOULD shoot better than 3/4ish MOA without having to go way way into seating depth work.

Maybe more details could be helpful for us on the rifle and load data you have etc!

 

[Haney]

I would go from "Touch" length and back of 10 . Hard jam minus 10 will still leave you in the lands usually .

 

[morning would]

Sharpie your bullets then find the lands with them. Much easier to see when you contact them without having to hit em so hard. Whenever ive done it this way, you can see the rifling start to leave marks parallel to the base and tip of bullet that look just like rifling. Very easy to see that way while BARELY contacting the lands.

Why jam so much? I doubt it will prove necessary fwiw. One notable exception is with bore riding cast bullets for me, but thats another animal.... anyways, It SUCKS to have to single load and then you pull a bullet and powder up the raceway... they dont stick now when its clean at home but Murphy... man he likes it dirty...

Have you tried any good factory match ammo to get a baseline? It SHOULD shoot better than 3/4ish MOA without having to go way way into seating depth work.

Maybe more details could be helpful for us on the rifle and load data you have etc!

Specs for the rifle and load are in my wall of text. For ease of seeing it, it’s an APF 6 ARC with proof carbon fiber barrel. Load is 24.8 grains of tac with a Berger 105. As for a baseline, there are only 4 factory loadings for 6 ARC. That’s it. .75 is the best it’ll shoot on a great day with any factory stuff. Most of the time it’s 1-1.25”. As for the sharpie trick, I’ll try that. Thank you.

I would go from "Touch" length and back of 10 . Hard jam minus 10 will still leave you in the lands usually .

Thanks, gonna back them out before I shoot them tomorrow.

 

[BuildingConceptsllc]

Specs for the rifle and load are in my wall of text. For ease of seeing it, it’s an APF 6 ARC with proof carbon fiber barrel. Load is 24.8 grains of tac with a Berger 105. As for a baseline, there are only 4 factory loadings for 6 ARC. That’s it. .75 is the best it’ll shoot on a great day with any factory stuff. Most of the time it’s 1-1.25”. As for the sharpie trick, I’ll try that. Thank you.

Thanks, gonna back them out before I shoot them tomorrow.

Don't take this the wrong way but, are you sure that it's the gun? I would think match factory ammo would shoot pretty decent

 

[Supersubes]

Those just looking like feeding marks to me, not lands engraving.

Dont single feed your AR, thats just dumb.

 

[morning would]

Don't take this the wrong way but, are you sure that it's the gun? I would think match factory ammo would shoot pretty decent

Fair question for sure. I’ve seen plenty of people that said they can shoot, that can’t. But yes, I’m sure it’s the rifle. Plenty of other rifles I can shoot .3’s or better under the right conditions in that I have already worked up loads for on a fairly consistent basis. Been shooting my entire life and started out shooting small bore back in high school in the 80’s. Ran all up and down the state of California competing. My skills aren’t my problem. At least not in this particular case. Put a pistol in my hand and it’s a whole different issue. That would definitely be me instead of the gun.

As for the factory match ammo in question. Plenty of people are finding out that after Hornady botched the 105’s early on, there may not be the best ammo out there right now by them. It’s what finally drove me to reloading. Not a lot of people that are shooting legitimate groups much less than an inch consistently. Every once in awhile, sure. But that’s not quite the same.

 

[morning would]

Those just looking like feeding marks to me, not lands engraving.

Dont single feed your AR, thats just dumb.

Dumb to do it regularly? Sure. But for what I’m doing with this particular work up, not as far as I’m concerned. Plenty of other rifles to stick a mag full in and go.

 

[morning would]

Anyways, I got my answer. I’m gonna back them off another .010 and go shoot them. We’ll see how that goes. Taking Haney’s advice as that is how I was leaning as well.

 

[Supersubes]

Dumb to do it regularly? Sure. But for what I’m doing with this particular work up, not as far as I’m concerned. Plenty of other rifles to stick a mag full in and go.

I have other guns too, but I wouldn't want to spend time and components turning an AR into a single shot. Youre not the only one who’s tried that, but that doesn't make it any less ridiculous.

 

[BuildingConceptsllc]

Fair question for sure. I’ve seen plenty of people that said they can shoot, that can’t. But yes, I’m sure it’s the rifle. Plenty of other rifles I can shoot .3’s or better under the right conditions in that I have already worked up loads for on a fairly consistent basis. Been shooting my entire life and started out shooting small bore back in high school in the 80’s. Ran all up and down the state of California competing. My skills aren’t my problem. At least not in this particular case. Put a pistol in my hand and it’s a whole different issue. That would definitely be me instead of the gun.

As for the factory match ammo in question. Plenty of people are finding out that after Hornady botched the 105’s early on, there may not be the best ammo out there right now by them. It’s what finally drove me to reloading. Not a lot of people that are shooting legitimate groups much less than an inch consistently. Every once in awhile, sure. But that’s not quite the same.

Roger that. Some guys expect to be able to shoot their gas gun like they do bolt guns right out of the gate and that's usually not the case so I had to ask. I guess there isn't any match ammo with a Sierra or Berger bullet?

 

[morning would]

Roger that. Some guys expect to be able to shoot their gas gun like they do bolt guns right out of the gate and that's usually not the case so I had to ask. I guess there isn't any match ammo with a Sierra or Berger bullet?

Negative. Only Hornady for now. Factory 103’s, 105’s, and 108’s commercially available and then a 106 TAP for the king’s men. Some guys are doing alright, but I have yet to see pics or even many videos with people showing off all their 1/2” groups with these consistently. Which is really the key for me. Sure, I don’t doubt some are doing better than others. I am just trying to shoot consistent .6’s or so from this AR. That would be a huge win for me. Who knows. Maybe .75 is the best it’ll do. But I’m just trying to test everything. Even single loading an AR for this test….

 

[Taylorbok]

If ur gonna single load just use a bolt gun. I agree that doesn't look like the lands. not sure what it's from but you can usually see the number of lands not a solid circle. Realistically who cares as long as it doesn't stick a bullet. Just keep adjusting it back until it shoots best.

 

[2aBaC̶a̶]

doesnt look like marks from being jammed. just your typical semi-auto beating up the round before it fires.

 

[Haney]

Don't take this the wrong way but, are you sure that it's the gun? I would think match factory ammo would shoot pretty decent

Have you ever shot "match factory ammo" ? It's not magical because of the name . Just like any load in any rifle , some pairings just don't work that well .

 

[Haney]

If ur gonna single load just use a bolt gun. I agree that doesn't look like the lands. not sure what it's from but you can usually see the number of lands not a solid circle. Realistically who cares as long as it doesn't stick a bullet. Just keep adjusting it back until it shoots best.

"If ur gonna single load just use a bolt gun" ...

That's laughable right there . Obviously you have no experience with AR platform and competition , etc . .

 

[BuildingConceptsllc]

Have you ever shot "match factory ammo" ? It's not magical because of the name . Just like any load in any rifle , some pairings just don't work that well .

Yes of course I have , but thanks for that pearl of wisdom

 

[Pete B]

Yeah, got to agree with some of these guys ..... that doesn't like like rifling being engraved on the round. Put some sharpie on it as stated, and try again.
Generally it will look square/retangular, not sure what you have going on there?

 

[ma smith]

That mark possibly looks like a seating die stem or ogive comparator etc,
ie, something circular going around the circumference of the bullet.

 

[Barelstroker]

So I have spent a metric shit ton of time researching loading depths based on using a modified case and the Hornady tool to find where the cartridge/bullet combo jams. I’ve seen all kinds of terminology, but no pics. So figured I’d ask a question on one of the most knowledgeable sites on the net, and use a pic for an example.

Rifle is an AR in 6 ARC. It’s built by APF with a CF Proof Research barrel. Found a few loads that get me to .7-ish at best, but I know it’s got more in it. Grabbed the OAL gauge and hard jammed a 105 Berger and came up with base to ogive of 1.718. Came off that hard jam by .010, so base to ogive is now 1.708, and single loaded it into a mag and sent the bolt home with the bolt release. Was trying to make sure that if it was going to stick, I’d have it happen at home where I can clean up the mess easier. Did this with 3 loaded rounds separately and none of them stuck a bullet. I assumed they wouldn’t, but I am trying to get these rounds as perfect as my ability allows. Anyways, all of them have marks on them. Marks that tell me it’s touching the lands, but not hanging up the bullet. 6 ARC is pretty finicky in how fast it builds pressure, so I am about 1.3 grains down from max at 24.8 grains of TAC. Just looking for advice, I know to take all of it in and every rifle is different, but just don’t want to blow shit up. Pretty sure I’m safe, but nobody around the net posts pics of what I’m talking about, so maybe this will help others someday in a search.

Generally speaking, when you are still touching the lands enough to make these marks, is that truly .010 off the lands? Or should I see absolutely zero marks on the bullet before it’s not considered “jamming“ the lands? I know this round does not fit in a mag and will have to single load from the top. I’m fine with that for paper punching. I’ll adjust later, maybe, to fit in a magazine if I choose to use this for anything more than a target shooter. Just trying to see how accurate I can truly get a load to be for this particular rifle.

I appreciate you guys taking a look at the pic, and giving me an education of what the correct terminology it is that I’m looking at.

I suggest you 1st determine if the case shoulder datum is hard against the chamber datum.
When most guys size their cases, it's generally assumed that the case shoulder is hard against the chamber shoulder which ensures a zero position for the projectile seating depth. (in the case of a plunger ejector bolt system)
From that position, any change in seating depth will be reflected directly due to the solid position of the case neck.
If, on the other hand, you have the situation where the case shoulder is a good ways from the chamber shoulder due to the projectile holding the case back & the plunger ejector taking up the rearward movement, this situation would give you a completely false sense of the increase in seating depth required to allow the plunger to push the case all the way to either the shoulder or the extractor claw, (which ever comes 1st)
In other words, measure the case headspace to see where you're at.
This is the only thing I can think of as to how the projectile can still be contacting the lands after an increase in seating depth.

 

[redbullitt]

Agree the marks look funny to be from rifling contact.

 

[morning would]

Sitting in line at the range now. Love me some hunting season. One thing is for sure, it’s not rifling. I jammed 10 other rifles and nothing leaves swirls like that. Gonna shoot it and see if it groups. If not, a call to Proof may be in order. Just want to make sure there isn’t a weird burr or something leaving that. I also see a borescope in my future.

 

[Cascade Hemi]

I suggest you 1st determine if the case shoulder datum is hard against the chamber datum.
When most guys size their cases, it's generally assumed that the case shoulder is hard against the chamber shoulder which ensures a zero position for the projectile seating depth. (in the case of a plunger ejector bolt system)
From that position, any change in seating depth will be reflected directly due to the solid position of the case neck.
If, on the other hand, you have the situation where the case shoulder is a good ways from the chamber shoulder due to the projectile holding the case back & the plunger ejector taking up the rearward movement, this situation would give you a completely false sense of the increase in seating depth required to allow the plunger to push the case all the way to either the shoulder or the extractor claw, (which ever comes 1st)
In other words, measure the case headspace to see where you're at.
This is the only thing I can think of as to how the projectile can still be contacting the lands after an increase in seating depth.

Exactly this. The Accuracy One seating depth gage is good for measuring ogive to shoulder. You can get a fairly accurate seating depth from a Hornady/SP tool. AR's always load the cartridge shoulder hard into the chamber shoulder assuming there is clearance between the bullet and throat.

 

[SMTGWKD]

Fair question for sure. I’ve seen plenty of people that said they can shoot, that can’t. But yes, I’m sure it’s the rifle. Plenty of other rifles I can shoot .3’s or better under the right conditions in that I have already worked up loads for on a fairly consistent basis. Been shooting my entire life and started out shooting small bore back in high school in the 80’s. Ran all up and down the state of California competing. My skills aren’t my problem. At least not in this particular case. Put a pistol in my hand and it’s a whole different issue. That would definitely be me instead of the gun.

As for the factory match ammo in question. Plenty of people are finding out that after Hornady botched the 105’s early on, there may not be the best ammo out there right now by them. It’s what finally drove me to reloading. Not a lot of people that are shooting legitimate groups much less than an inch consistently. Every once in awhile, sure. But that’s not quite the same.

FWIW - I agree that there aren't a bunch of videos/posting showing great groups for the ARC - I find the same thing with the Q Fix. However, owning both with Proof CF barrels (18" ARC and 16" 6.5 Creed) I've had great accuracy into sub .5 moa groups with each, but had to find the bullet/powder combo they liked best. Wasn't difficult, just took a willingness to try a few combos.

For an added data point, my ARC likes 108s best and easily shoots factory Hornady 108 ELD M inside 1". I like temp stability and run 26.8 of Varget with 108s and 3-5 shot groups range from .295 -.564" at 100 yards. Jump doesn't seem to matter much as I'm just loading to factory specs.

As a side note, I'm sure you have no issues with semi auto mechanics, but some of my AR's exhibit noticeable vertical changes with bipod pressure on the handguard. I have far less experience than pretty much everyone on here, but I've had to become more aware and consistent in my bipod loading or the group's suffer by .5" or more. My 18" ARC is in a Radian Builder set and doesn't seem to care much about bipod pressure.

 

[morning would]

FWIW - I agree that there aren't a bunch of videos/posting showing great groups for the ARC - I find the same thing with the Q Fix. However, owning both with Proof CF barrels (18" ARC and 16" 6.5 Creed) I've had great accuracy into sub .5 moa groups with each, but had to find the bullet/powder combo they liked best. Wasn't difficult, just took a willingness to try a few combos.

For an added data point, my ARC likes 108s best and easily shoots factory Hornady 108 ELD M inside 1". I like temp stability and run 26.8 of Varget with 108s and 3-5 shot groups range from .295 -.564" at 100 yards. Jump doesn't seem to matter much as I'm just loading to factory specs.

As a side note, I'm sure you have no issues with semi auto mechanics, but some of my AR's exhibit noticeable vertical changes with bipod pressure on the handguard. I have far less experience than pretty much everyone on here, but I've had to become more aware and consistent in my bipod loading or the group's suffer by .5" or more. My 18" ARC is in a Radian Builder set and doesn't seem to care much about bipod pressure.

Appreciate the input And will give that load of Varget a try.

I’ve been out a couple times and shooting the original loads that started this thread proved to be pretty damn accurate. Single loaded and all. So since I knew the gun could shoot, I buckled down and concentrated on loading just for this. Stumbled upon 26.1 grains of Shooters World Precision and a Hornady 108 ELD loaded out to standard magazine lengths and now have multiple groups in the .4’s and a .342. I also have shot a .407 with 25.5 that I need to make some confirmation loads for to double check it. But it looks like a damn big node there for me between there and the 26.1 load. I’ve also been playing with 95gr Bergers as well and have a found a couple different loads with TAC, CFE223 and Lever that are anywhere from .745 down to .435 with a CCI 450 and 28.0gr of CFE with a BTO of 1.682”. TAC with 105 bergers and CCI 450 at both 24.8 and 25.7 at 1.7“ BTO have shown promise with a .425 and .495 respectively. As you can see, I’ve been busy (see obsessed) with getting this upper dialed in. Still no idea what those rings on the bullet that started this whole thread are, but it really doesn’t matter anymore now that I am so far out anyways. A few of the recent results….

 

[SMTGWKD]

Appreciate the input And will give that load of Varget a try.

I’ve been out a couple times and shooting the original loads that started this thread proved to be pretty damn accurate. Single loaded and all. So since I knew the gun could shoot, I buckled down and concentrated on loading just for this. Stumbled upon 26.1 grains of Shooters World Precision and a Hornady 108 ELD loaded out to standard magazine lengths and now have multiple groups in the .4’s and a .342. I also have shot a .407 with 25.5 that I need to make some confirmation loads for to double check it. But it looks like a damn big node there for me between there and the 26.1 load. I’ve also been playing with 95gr Bergers as well and have a found a couple different loads with TAC, CFE223 and Lever that are anywhere from .745 down to .435 with a CCI 450 and 28.0gr of CFE with a BTO of 1.682”. TAC with 105 bergers and CCI 450 at both 24.8 and 25.7 at 1.7“ BTO have shown promise with a .425 and .495 respectively. As you can see, I’ve been busy (see obsessed) with getting this upper dialed in. Still no idea what those rings on the bullet that started this whole thread are, but it really doesn’t matter anymore now that I am so far out anyways. A few of the recent results….

Great input and results! Did you track velocities for those loads?